Whilst the Southern Electricity Board was a distribution-only authority, with no power generation capacity of its own, the North of Scotland Hydro-Electric board was a broader spectrum organisation, with its own generating capabilities. Because of its history and location, the Hydro-Electric Board was responsible for most of the UK's hydroelectric generating capacity.

Both authorities were privatised in 1990/91, initially retaining their pre-privatisation geographic and functional bases. The North of Scotland Hydro-Electric Board became Scottish Hydro-Electric, whilst the Southern Electricity Board became Southern Electric.

The company is the second largest supplier of electricity and natural gas in the United Kingdom, and the UK's largest generator of renewable energy.[10] It incorporates the brands SWALEC, Southern Electric, Scottish Hydro Electric and Atlantic Electric and Gas. It also owns Southern Electric Power Distribution, Scottish Hydro Electric Power Distribution and Scottish Hydro Electric Transmission. Its subsidiaries are organised into the main businesses of generation, transmission, distribution and supply of electricity; storage and supply of gas; electrical and utility contracting, and domestic appliance retailing and telecoms. They also own Airtricity.[6]

SSE also has an equity interest of 50% in, and provides corporate and management services to Scotia Gas Networks, which owns Southern Gas Networks and Scotland Gas Networks. Its contracting business has five main areas of activity: industrial, commercial and domestic, mechanical and electrical contracting; data communications; high-voltage design and maintenance; electrical and instrumentation engineering, and public and highway lighting.

In March 2014, SSE withdrew investment in four major offshore wind farms. It plans to sell its stake in the Galloper wind farm and pull investment from the Islay, Dogger Bank and Firth of Forth wind farms. SSE blamed "limited subsidies and high costs".[11]

SSE is the UK's largest officially-accredited Living Wage Employer. Nearly 20,000 staff across the UK are guaranteed to receive the living wage rate of at least £7.85 an hour. [12] SSE works closely with the Living Wage Foundation and was awarded the Living Wage Champion Award for Scotland in 2014.

In October 2014 SSE became the first FTSE 100 company to be awarded the Fair Tax Mark which is an independent accreditation process for identifying companies making an effort to be transparent about their tax affairs. [13]

The SSE Hydro is an arena located in Glasgow, Scotland, on the site of the Scottish Exhibition and Conference Centre (SECC). The arena officially opened on 30 September 2013 and has a capacity of 13,000. It was designed by the London-based architects Foster + Partners. The SSE Hydro hosts international musical stars, global entertainment and sporting events, with an aim to attract one million visitors each year.